Hindawi Publishing Corporation Journal of Applied Mathematics Volume 2012, Article ID 824265, 16 pages doi:10.1155/2012/824265 Research Article Evaluating Projects Based on Intuitionistic Fuzzy Group Decision Making Babak Daneshvar Rouyendegh1, 2 1 2 Department of Industrial Engineering, Atilim University, P.O. Box 06836, Incek, Ankara, Turkey Department of Mechanical & Industrial Engineering, University of Toronto, Toronto, ON, Canada M5S 3G8 Correspondence should be addressed to Babak Daneshvar Rouyendegh, babekd@atilim.edu.tr Received 9 November 2011; Revised 30 January 2012; Accepted 27 March 2012 Academic Editor: Luis Javier Herrera Copyright q 2012 Babak Daneshvar Rouyendegh. This is an open access article distributed under the Creative Commons Attribution License, which permits unrestricted use, distribution, and reproduction in any medium, provided the original work is properly cited. There are various methods regarding project selection in different fields. This paper deals with an actual application of construction project selection, using two aggregation operators. First, the opinion of experts is used in a model of group decision making called intuitionistic fuzzy TOPSIS IFT. Secondly, project evaluation is formulated by dynamic intuitionistic fuzzy weighted averaging DIFWA. Intuitionistic fuzzy weighted averaging IFWA operator is utilized to aggregate individual opinions of decision makers DMs for rating the importance of criteria and alternatives. A numerical example for project selection is given to clarify the main developed result in this paper. 1. Introduction Project selection and project evaluation involve decisions that are critical in terms of the profitability, growth, and survival of project management organizations in the increasingly competitive global scenario. Such decisions are often complex, because they require identification, consideration, and analysis of many tangible and intangible factors 1. There are various methods regarding project selection in different fields. Project selection problem has attracted great endeavor by practitioners and academicians in recent years. One of the major fields that have been applied to this problem is mathematical programming, especially Mix-Integer Programming MIP, since the problems comprise selection of projects while other aspects are considered using real-value variables 2. For instance, a MIP model is developed by 3 to conquer Research and Development R&D portfolio selection. Multicriteria decision making MCDM is a modeling and methodological tool for dealing with complex engineering problems 4. Many mathematical programming models 2 Journal of Applied Mathematics have been developed to address project-selection problems. However, in recent years, MCDM methods have gained considerable acceptance for judging different proposals. The objective of Mohanty’s 5 study was to integrate the multidimensional issues in an MCDM framework that may help decision makers to develop insights and make decisions. They computed weight of each criterion and then assessed the projects by doing technique for order preference by similarity to ideal solution algorithm TOPSIS 6. To select R&D project, the application of the fuzzy analytical network process ANP and fuzzy cost analysis has been used by some researchers 7. In their studies, triangular fuzzy numbers TFNs are used to prefer one criterion over another by using a pairwise comparison with the fuzzy set theory, where the weight of each criterion in the format of triangular fuzzy numbers is calculated 7. The project selection problem was presented through a methodology which is based on the analytic hierarchy process AHP for quantitative and qualitative aspects of a problem 8. It assists the measuring of the initial viability of industrial projects. The study shows that industrial investment company should concentrate its efforts in development of prefeasibility studies for a specific number of industrial projects which have a high likelihood of realization 8. Multiattribute decision making MADM is the other applied approach in which criteria are mostly defined in qualitative scale and the decision is made with respect to assigned weights using some methods, such as PROMETHEE 9, 10. To have more comprehensive study on MADM methods in this field, readers are referred to 11–15. The rest of the paper is organized as follows. Section 2 provides materials and methods, mainly fuzzy set theory FST and intuitionistic fuzzy set IFS. The IFT and DIFWA are introduced in Section 3. How the proposed model is used in an actual example is explained in Section 4. Finally, the conclusions are provided in the final section. 2. Materials and Methods 2.1. FST Zadeh 1965 introduced the fuzzy set theory FST to deal with the uncertainty due to imprecision and vagueness. A major contribution of this theory is capability of representing vague data; it also allows mathematical operators and programming to be applied to the fuzzy domain. An FS is a class of objects with a continuum of grades of membership. Such a set is characterized by a membership function, which assigns to each object a grade of membership ranging between zero and one 16, 17. is A tilde “∼” will be placed above a symbol if the symbol represents an FST. A TFN M shown in Figure 1. A TFN is denoted simply as l/m, m/u or l, m, u. The parameters l, m and u l ≤ m ≤ u, respectively, denote the smallest possible value, the most promising value, and the largest possible value that describe a fuzzy event. The membership function of TFN is as follows. Each TFN has linear representations on its left and right side, such that its membership function can be defined as ⎧ ⎪ 0, x < l, ⎪ ⎪ ⎪ ⎪ x − l ⎪ ⎪ ⎪ ⎨ m − l , l ≤ x ≤ m, x 2.1 μ ⎪ u−x ⎪ M ⎪ , m ≤ x ≤ u, ⎪ ⎪ u−m ⎪ ⎪ ⎪ ⎩ 0, x > u. Journal of Applied Mathematics 3 1 Ml(y) 0 Mr(y) l m u Figure 1: A TFN M. A fuzzy number can always be given by its corresponding left and right representation of each degree of membership as in the following: Mly , Mry l m − ly, u m − uy , M y ∈ 0, 1, 2.2 where ly and ry denote the left side representation and the right side representation of a fuzzy number FN, respectively. Many ranking methods for FNs have been developed in the literature. These methods may provide different ranking results, and most of them are tedious in graphic manipulation requiring complex mathematical calculation 18. While there are various operations on TFNs, only the important operations used in this study are illustrated. If we define two positive TFNs l1, m1, u1 and l2, m2, u2, then l1, m1, u1 l2, m2, u2 l1 l2, m1 m2, u1 u2, l1, m1, u1 ∗ l2, m2, u2 l1 ∗ l2, m1 m2, u1 ∗ u2, l1, m1, u1 k l1 ∗ km1 ∗ k, u1 ∗ k, 2.3 where k > 0. 2.2. Basic Concept of IFS The application of IFS method within the overall goal to select the best project has been described. IFSs introduced by Atanassov 19 are an extension of the classical FST, which is a suitable way to deal with vagueness. IFSs have been applied to many areas such as medical diagnosis 20–22, decision-making problems 23–46, pattern recognition 47–52, supplier selection 53, 54, enterprise partners selection 55, personnel selection 56, evaluation of renewable energy 57, facility location selection 58, web service selection 59, printed circuit board assembly 60, and management information system 61. The following briefly introduces some necessary introductory concepts of IFS. IFS A in a finite set X can be written as 19 A x, μA x, vA x | x ∈ X , where μA x, VA x : X −→ 0, 1 2.4 are membership function and nonmembership function, respectively, such that 0 ≤ μA x VA x ≤ 1. 2.5 4 Journal of Applied Mathematics A third parameter of IFS is πA x, known as the intuitionistic fuzzy index or hesitation degree of whether x belongs to A or not: πA x 1 − μA x − VA x. 2.6 It is obviously seen that for every x ∈ X 0 ≤ πA x ≤ 1 if the πA x. 2.7 If it is small, knowledge about x is more certain. If πA x is great, knowledge about x is more uncertain. Obviously, when μA x 1 − vA xμA x 1 − vx 2.8 for all elements of the universe, the ordinary FST concept is recovered 60. Let A and B be IFSs of the set X, then multiplication operator is defined as follows 19: A B μA x · μB x, vA x vB x − vA x · vB x | x ∈ X . 2.9 3. Intuitionistic Fuzzy TOPSIS (IFT) and Dynamic Intuitionistic Fuzzy Weighted Averaging (DIFWA) Methods 3.1. IFT It should be mentioned here that the presented approach mainly utilizes the IFT method presented in 53, 56, 57 to handle a project selection problem with six projects and six criteria. In the current paper we validate the method in an actual context and show this method applicability with an extensive set of selection criteria. The IFT method is a suitable way to deal with MCDM problem in intuitionistic fuzzy environment IFE. Let A {A1 , A2 , . . . , Am } be a set of alternatives and let X {X1 , X2 , . . . , Xn } be a set of criteria, the procedure for IFT method has been conducted in eight steps presented as follows. Step 1. Determine the weights of importance of DMs. In the first step, we assume that decision group contains l {l1 , l2 , . . . , ln } DMs. The importances of the DMs are considered as linguistic terms. These linguistic terms were assigned to IFN. Let Dk μk , vk , πk be an intuitionistic fuzzy number for rating of kth DM.Then the weight of kth DM can be calculated as μk πk μk / μk vk λk l , k1 μk πk μk / μk vk where λk ∈ 0, 1, l λk 1. 3.1 k1 Step 2. Determine intuitionistic fuzzy decision matrix IFDM. Based on the weight of DMs, the aggregated intuitionistic fuzzy decision matrix AIFDM was calculated by applying intuitionistic fuzzy weighted averaging IFWA Journal of Applied Mathematics 5 operator Xu 62. In group decision-making process, all the individual decision opinions need to be fused into a group opinion to construct AIFDM. k Let Rk rij m×n be an IFDM of each DM. λ {λ1 , λ2 , λ3 , . . . , λl } is the weight of DM. Consider R rij m×n , 3.2 where rij IFWAλ rij 1 , rij 2 , . . . , rij l λ1 rij 1 λ2 rij 2 λ3 rij 3 ··· λl rij l l l l l λ λ λ λ k k k k k k k k . 1 − μij vij 1 − μij vij 1− , , − k1 k1 k1 3.3 k1 Step 3. Determine the weights of the selection criteria. In this step, all criteria may not be assumed to be of equal importance. W represents a set of grades of importance. In order to obtain W, all the individual DM opinions for the importance of each criteria need to be fused. Let wj k μj k , vj k , πj k be an IFN assigned to criterion Xj by the kth DM. The weights of the criteria can be calculated as follows: λ2 wj 2 λ3 wj 3 ··· λl wj l wj IFWAλ wj 1 , wj 2 , . . . , wj l λ1 wj 1 1− l 1 − μj k l l l λ k λ λ λ k k k k k k . vj 1 − μj vj , , − k1 k1 k1 3.4 k1 Thus, a vector of criteria weight is obtained: W w1 , w2 , w3 , . . . , wj , where wj μj , vj , πj j 1, 2, . . . , n. Step 4. Construct the aggregated weighted IFDM. In Step 4, the weights of criteria W and the aggregated IFDM are determined to the aggregated weighted IFDM which is constructed according to the following definition 19: R R W μij , vij x, μij · μj , vij vj − vij · vj , πij 1 − vij − vj − μij · μj vij · vj . 3.5 R is a matrix composed with elements IFNs, rıj μij , vij , πij i 1, 2, . . . , m; j 1, 2, . . . , n. 6 Journal of Applied Mathematics Step 5. Determine intuitionistic fuzzy positive and negative ideal solution. In this step, the intuitionistic fuzzy positive ideal solution IFPIS and intuitionistic fuzzy negative ideal solution IFNIS have to be determined. Let J1 and J2 be benefit criteria and cost criteria, respectively. A∗ is IFPIS and A− is IFNIS. Then A∗ and A− are equal to ∗ ∗ ∗ A∗ r1 , r2 , . . . , rn , − − − A− r1 , r2 , . . . , rn , ∗ ∗ ∗ ∗ rj μj , vj , πj , j 1, 2, . . . , n, − − − − rj μj , vj , πj , j 1, 2, . . . , n, 3.6 where ∗ μj max μij j ∈ J1 , min μij j ∈ J2 , i i min vij j ∈ J1 , max vij j ∈ J2 vj∗ , i πj ∗ i i − μj vj − i 1 − max μij − min vij j ∈ J1 , 1 − min μij − max vij j ∈ J2 , πj − i i min μij j ∈ J1 , max μij j ∈ J2 , i 3.7 i max vij j ∈ J1 , min vij j ∈ J2 , i i 1 − min μij − max vij j ∈ J1 , 1 − max μij − min vij j ∈ J2 . i i i i Step 6. Determine the separation measures between the alternative. Separation between alternatives on IFS, distance measures proposed by Atanassov 63, Szmidt and Kacprzyk 64, and Grzegorzewski 65 including the generalizations of Hamming distance, Euclidean distance and their normalized distance measures can be used. After selecting the distance measure, the separation measures, S∗i and S−i , of each alternative from IFPIS and IFNIS, are calculated: S∗i S−i n 1 ∗ ∗ ∗ μij − μj vij − vj πij − πj , 2 j1 n 1 − − − μij − μj vij − vj πij − πj . 2 j1 3.8 Step 7. Determine the final ranking. In the final step, the relative closeness coefficient of an alternative Ai with respect to the IFPIS A∗ is defined as follows: Ci∗ S−i S∗i S−i , where 0 ≤ Ci∗ ≤ 1. The alternatives were ranked according to descending order of Ci∗ ’s score. 3.9 Journal of Applied Mathematics 7 3.2. DIFWA The DIFWA method, proposed by Xu and Yager 33, is a suitable way to deal with problem in IFE. The procedure for DIFWA method has been given as follows. Step 1. Utilize the DIFWA operator rij DIFWAλt rij t1 , rij t2 , . . . , rij tp p p p p λtk λtk λtk λtk 1 − μrij tk 1 − μrij tk , vrij tk , − vrij tk . 1− k1 k1 k1 3.10 k1 to aggregate all the intuitionistic fuzzy matrix Rtk rij tk m×n k 1, 2, . . . , p into a complex IFDM: where rij μij , vij , πij , R rij m×n , μij 1 − p 1 − μrij tk λtk , vij k1 πij p 1 − μrij tk p k1 λtk k1 − p k1 i 1, 2, . . . , n, λt vrij tkk , 3.11 λt vrij tkk , j 1, 2, . . . , m. Step 2. Define α α1 , α2 , . . . , αm T and α− α−1 , α−2 , . . . , α−m T as the IFPIS and the IFNIS, respectively, where α 1, 0, 0 i 1, 2, . . . , m are the m largest IFNs and α− 0, 1, 0 i 1, 2, . . . , m are the m smallest IFNs. Furthermore, for convenience of depiction, we denote the alternative xi i 1, 2, . . . , n by xi ri1 , ri2 , . . . , rim T , i 1, 2, . . . , n. Step 3. Calculate the distance between the alternative xi and the IFIS and the distance between the largest native xi and the IFNIS, respectively: dxi , α m m 1 wj d rij , αj wj μij − 1 vij − 0 πij − 0 2 j1 j1 m m 1 1 wj 1 − μij vij πij wj 1 − μij vij 1 − μij − vij 2 j1 2 j1 m wj 1 − μij , j1 m m 1 d xi , α− wj d rij , α−j wj μij − 0 vij − 1 πij − 0 2 j1 j1 8 Journal of Applied Mathematics m m 1 1 wj 1 − μij − vij πij wj 1 μij − vij 1 − μij − vij 2 j1 2 j1 m wj 1 − vij , j1 3.12 where rij μij , vij , πij , i 1, 2, . . . , n, j 1, 2, . . . , m. Step 4. Calculate the closeness coefficient of each alternative: cxi dxi , α− , dxi , α dxi , α− i 1, 2, . . . , n. 3.13 Since m m m m dxi , α d xi , α− wj 1 − μij wj 1 − vij wj 2 − μij − vij wj 1 πij , j1 j1 j1 j1 3.14 then 3.13 can be rewritten as m cxi j1 wj 1 − vij , m j1 wj 1 − πij i 1, 2, . . . , n. 3.15 Step 5. Rank all the alternatives xi 1, 2, . . . , n according to the closeness coefficients cxi 1, 2, . . . , n, the greater the value cxi , the better the alternative xi . 4. Case Study In this section, we will describe how an IFT method was applied via an example of selection of the most appropriate projects. Criteria to be considered in the selection of projects are determined by the expert team from a construction group. In our study, we employ six evaluation criteria. The attributes which are considered here in assessment of Pi i 1, 2, . . . , 6 are 1 C1 is benefit and 2 C2 , . . . , C6 are cost. The committee evaluates the performance of projects Pi i 1, 2, . . . , 6 according to the attributes Cj j 1, 2, . . . , 6, respectively. Criteria are mainly considered as follows i net present value C1 , ii quality C2 , iii duration C3 , iv contractor’s rank C4 , v contractor’s technology C5 , vi contractor’s economic status C6 . Journal of Applied Mathematics 9 Table 1: Linguistic term for rating DMs. Linguistic terms IFNs Very important Important Medium Bad Very Bad 0.80, 0.10 0.50, 0.20 0.50, 0.50 0.3, 0.50 0.20, 0.70 Table 2: The importance of DMs and their weights. Linguistic terms Weight DM1 DM2 DM3 DM4 Very important 0.342 Medium 0.274 Important 0.192 Important 0.192 Therefore, one cost criterion, C1 and five benefit criteria, C2 , . . . , C6 are considered. After preliminary screening, six projects P1 , P2 , P3 , P4 , P5 , and P6 remain for further evaluation. A team of four DMs such as DM1 , DM2 , DM3 , and DM4 has been formed to select the most suitable project. Now utilizing the proposed IFT to prioritize these construction projects, the following steps were taken. Degree of the DMs on group decision, shown in Table 1, and linguistic terms used for the ratings of the DMs and criteria, as Table 2, respectively. Construct the aggregated IFDM based on the opinions of DMs and the linguistic terms shown in Table 3. The ratings given by the DMs to six projects were shown in Table 4. The aggregated IFDM based on aggregation of DMs’ opinions was constructed as follows: A1 A2 A R 3 A4 A5 A6 C1 ⎡ 0.80, 0.08, 0.12 ⎢0.68, 0.20, 0.12 ⎢ ⎢0.82, 0.07, 0.11 ⎢ ⎢ ⎢ 0.83, 0.16, 0.1 ⎢ ⎣0.55, 0.38, 0.07 0.75, 0.13, 0.12 C4 A1 A2 A × 3 A4 A5 A6 C2 0.69, 0.20, 0.11 0.78, 0.11, 0.11 0.79, 0.10, 0.11 0.75, 0.14, 0.11 0.42, 0.52, 0.06 0.69, 0.19, 0.12 ⎡ 0.80, 0.09, 0.11 ⎢0.78, 0.11, 0.11 ⎢ ⎢0.84, 0.05, 0.11 ⎢ ⎢ ⎢0.81, 0.08, 0.11 ⎢ ⎣0.55, 0.33, 0.12 0.75, 0.13, 0.12 C3 ⎤ 0.76, 0.12, 0.12 0.74, 0.13, 0.13⎥ ⎥ 0.79, 0.10, 0.11⎥ ⎥ ⎥ 0.70, 0.19, 0.11⎥ ⎥ 0.64, 0.40, 0.06⎦ 0.75, 0.13, 0.12 C5 0.78, 0.11, 0.11 0.69, 0.21, 0.10 0.84, 0.05, 0.11 0.82, 0.07, 0.11 0.54, 0.33, 0.13 0.85, 0.05, 0.10 C6 4.1 ⎤ 0.69, 0.20, 0.11 0.75, 0.13, 0.12⎥ ⎥ 0.84, 0.05, 0.11⎥ ⎥ ⎥. 0.85, 0.05, 0.10⎥ ⎥ 0.40, 0.54, 0.06⎦ 0.78, 0.11, 0.11 The linguistic terms shown in Table 5 were used to rate each criterion. The importance of the criteria represented as linguistic terms was shown in Table 6. 10 Journal of Applied Mathematics Table 3: Linguistic terms for rating the alternatives. Linguistic terms IFNs Extremely good EG Very good VG Good G Medium bad MB Bad B Very bad VB Extremely bad EB 1.00; 0.00; 0.00 0.85; 0.05; 0.10 0.70; 0.20; 0.10 0.50; 0.50; 0.00 0.40; 0.50; 0.10 0.25; 0.60; 0.15 0.00, 0.90,0.10 The opinions of DMs on criteria were aggregated to determine the weight of each criterion: W{X1 ,X2 ,X3 ,X4 ,X5 ,X6 } ⎡ ⎤T 0, 71, 0.19, 0.10 ⎢0, 90, 0.00, 0.10⎥ ⎢ ⎥ ⎢0, 65, 0.27, 0.80⎥ ⎢ ⎥ ⎢ ⎥ . ⎢0, 78, 0.11, 0.11⎥ ⎢ ⎥ ⎣0, 80, 0.10, 0.10⎦ 0, 67, 0.24, 0.9 4.2 After the weights of the criteria and the rating of the projects were determined, the aggregated weighted IFDM was constructed as follows: A1 A2 A R 3 A4 A5 A6 C1 ⎡ 0.57, 0.26, 0.18 ⎢0.48, 0.35, 0.17 ⎢ ⎢0.58, 0.25, 0.17 ⎢ ⎢ ⎢0.59, 0.32, 0.09 ⎢ ⎣0.39, 0.50, 0.11 0.53, 0.30, 0.17 C2 0.62, 0.20, 0.18 0.70, 0.11, 0.19 0.70, 0.10, 0.19 0.70, 0.14, 0.19 0.38, 0.52, 0.10 0.62, 0.19, 0.19 C3 ⎤ 0.49, 0.36, 0.19 0.48, 0.37, 0.15⎥ ⎥ 0.51, 0.34, 0.14⎥ ⎥ ⎥ 0.45, 0.41, 0.14⎥ ⎥ 0.42, 0.56, 0.02⎦ 0.49, 0.36, 0.15 4.3 C4 A1 A2 A × 3 A4 A5 A6 ⎡ 0.62, 0.19, 0.19 ⎢0.61, 0.21, 0.18 ⎢ ⎢0.66, 0.16, 0.19 ⎢ ⎢ ⎢0.63, 0.18, 0.19 ⎢ ⎣0.43, 0.40, 0.17 0.59, 0.23, 0.19 C5 0.62, 0.20, 0.18 0.55, 0.29, 0.16 0.67, 0.15, 0.18 0.57, 0.16, 0.18 0.43, 0.40, 0.17 0.70, 0.14, 0.18 C6 ⎤ 0.46, 0.39, 0.15 0.50, 0.34, 0.16⎥ ⎥ 0.56, 0.28, 0.16⎥ ⎥ ⎥. 0.57, 0.28, 0.15⎥ ⎥ 0.27, 0.65, 0.08⎦ 0.52, 0.33, 0.15 The net present value is cost criteria j1 {X1 }, and quality, duration, contractor’s rank, contractor’s technology, and contractor’s economic status are benefit criteria j1 {X2 , X3 , X4 , X5 }. Journal of Applied Mathematics 11 Table 4: The ratings of the projects. Alternative Criteria C1 C2 C3 C4 C5 C6 C1 C2 C3 C4 C5 C6 C1 C2 C3 C4 C5 C6 C1 C2 C3 C4 C5 C6 C1 C2 C3 C4 C5 C6 C1 C2 C3 C4 C5 C6 P1 P2 P3 P4 P5 P6 DM1 VG G VG VG VG G G VG VG VG G VG VG VG VG VG VG VG MB G MB VG VG VG G MB B MB B MB VG G VG VG VG VG DM2 VG VG G VG VG VG VG VG VG VG G VG VG G G VG VG VG G VG VG G VG VG MB B G B MB VB VG VG VG VG VG VG DM3 G MB B G MB MB MB G B MB G MB G G VG VG VG VG MB G G VG G VG MB B MB VB VB VB MB B B B VB G DM4 G MB VG G G MB B MB B G G B VG VG G VG VG VG VG G G VG VG VG VB VB VG VG VG MB MB MB MB MB VG MB Then IFPIS and IFNIS were provided as follows: A∗ {0.59, 0.25, 0.16, 0.71, 0.10, 0.19, 0.51, 0.34, 0.15, 0.66, 0.15, 0.18, 0.68, 0.14, 0.18, 0.57, 0.28, 0.15}, − A {0.39, 0.5, 0.11, 0.38, 0.5, 0.12, 0.42, 0.56, 0.02, 0.43, 0.4, 0.17, 0.43, 0.4, 0.17, 0.27, 0.65, 0.08}. 4.4 12 Journal of Applied Mathematics Table 5: The linguistic terms for the importance of the criteria. Linguistic terms IFNs Very good VG Good G Medium good G Very bad VB Bad B 0.80; 0.10 0.50; 0.20 0.50; 0.50 0.30; 0.50 0.20; 0.60 Table 6: The importance weight of the criteria. Criteria DM1 DM2 DM3 DM4 C1 C2 C3 C4 C5 C6 G VG MB G G MB VG VG G G VG G VG VG VG VG MB MB MB VG MB G G VG Negative and positive separation measures based on normalized Euclidean distance for each project and the relative closeness coefficient were calculated in Table 7. Six projects were ranked according to descending order of Ci∗ ’s. The result score is always the bigger the better. As visible in Table 6, project 3 has the largest score, and project 5 has the smallest score of the six projects which is ranked in the last pace. The projects were ranked as P3 > P4 > P6 > P1 > P2 > P5 . Project 3 was selected as appropriate project among the alternatives. In the second part, we utilize the proposed DIFWA to prioritize these construction projects, and the following steps were taken. First, utilize the DIFWA to aggregate all the IFDM Rtk into a complex IFDM R: A1 A2 A R 3 A4 A5 A6 C1 ⎡ 0.57, 0.26, 0.18 ⎢0.48, 0.35, 0.17 ⎢ ⎢0.58, 0.25, 0.17 ⎢ ⎢ ⎢0.59, 0.32, 0.09 ⎢ ⎣0.39, 0.50, 0.11 0.53, 0.30, 0.17 C2 0.62, 0.20, 0.18 0.70, 0.11, 0.19 0.70, 0.10, 0.19 0.70, 0.14, 0.19 0.38, 0.52, 0.10 0.62, 0.19, 0.19 C3 ⎤ 0.49, 0.36, 0.19 0.48, 0.37, 0.15⎥ ⎥ 0.51, 0.34, 0.14⎥ ⎥ ⎥ 0.45, 0.41, 0.14⎥ ⎥ 0.42, 0.56, 0.02⎦ 0.49, 0.36, 0.15 4.5 C4 A1 A2 A × 3 A4 A5 A6 ⎡ 0.62, 0.19, 0.19 ⎢0.61, 0.21, 0.18 ⎢ ⎢0.66, 0.16, 0.19 ⎢ ⎢ ⎢0.63, 0.18, 0.19 ⎢ ⎣0.43, 0.40, 0.17 0.59, 0.23, 0.19 C5 0.62, 0.20, 0.18 0.55, 0.29, 0.16 0.67, 0.15, 0.18 0.57, 0.16, 0.18 0.43, 0.40, 0.17 0.70, 0.14, 0.18 C6 ⎤ 0.46, 0.39, 0.15 0.50, 0.34, 0.16⎥ ⎥ 0.56, 0.28, 0.16⎥ ⎥ ⎥. 0.57, 0.28, 0.15⎥ ⎥ 0.27, 0.65, 0.08⎦ 0.52, 0.33, 0.15 Journal of Applied Mathematics 13 Table 7: Separation measures and the relative closeness coefficient of each project. Alternatives P1 P2 P3 P4 P5 P6 S∗ S− Ci ∗ 0.36 0.42 0.04 0.23 0.18 0.3 1.38 1.35 1.73 1.54 0.02 1.46 0.79 0.77 0.98 0.87 0.01 0.83 Denote the IFIS, IFNIS, and the alternatives by α 1, 0, 0, 1, 0, 0, 1, 0, 0T , α− 0, 1, 0, 0, 1, 0, 0, 1, 0T , 4.6 and calculate the closeness coefficient of each alternative: CP1 0.622, CP2 0.618, CP3 0.671, CP4 0.650, CP5 0.447, CP6 0.633. 4.7 Rank all the projects according to the closeness coefficients. The projects were ranked as CP3 > CP4 > CP6 > CP1 > CP2 > CP5 . The greater value of CXi , the better alternative; thus the best alternative is also project 3. 5. Conclusion The IFT and DIFWA have been emphasized in this paper which occurs in construction projects evaluation. In the evaluation process, the ratings of each project, given with intuitionistic fuzzy information, were represented as IFNs. The IFWA operator was used to aggregate the rating of DM. In project selection problem the project’s information and performance are usually uncertain. Therefore, the decision makers are unable to express their judgment on the project with crisp value, and the evaluations are very often expressed in linguistic terms. IFT and DIFWA are suitable ways to deal with MCDM because it contains a vague perception of DMs’ opinions. An actual life example in construction sector was illustrated, and finally the result is as follows Among 6 construction projects with respect to 6 criteria, after using these two methods, the best one is project 3 and project 4, project 6, project 1, project 2, project 5 will follow it, respectively. The presented approach not only validates the methods, as it was originally defined in Boran and Xu in a new application field that was the evaluation of construction projects, but also considers a more extensive list of benefit and cost-oriented criteria, suitable for construction project selection. Finally, the IFT and DIFWA methods have capability to deal with similar types of the same situations with uncertainty in MCDM problems such as ERP software selection and many other areas. Acknowledgment The author is very grateful to the anonymous referees for their constructive comments and suggestions that led to an improved version of this paper. 14 Journal of Applied Mathematics References 1 J. Dodangeh, M. Mojahed, and R. B. M. Yusuff, “Best project selection by using of Group TOPSIS method,” in Proceedings of the International Association of Computer Science and Information Technology (IACSIT-SC ’09), pp. 50–53, April 2009. 2 J. Wang and W. L. Hwang, “A fuzzy set approach for R&D portfolio selection using a real options valuation model,” Omega, vol. 35, no. 3, pp. 247–257, 2007. 3 G. J. Beaujon, S. P. Marin, and G. C. McDonald, “Balancing and optimizing a portfolio of R&D projects,” Naval Research Logistics, vol. 48, no. 1, pp. 18–40, 2001. 4 B. D. Rouyendegh, “The DEA and intuitionistic fuzzy TOPSIS approach to departments’ performances: a pilot study,” Journal of Applied Mathematics, vol. 2011, Article ID 712194, 16 pages, 2011. 5 R. Mohanty, “Project selection by a multiple-criteria decision-making method: an example from a developing country,” International Journal of Project Management, vol. 10, no. 1, pp. 31–38, 1992. 6 S. Mahmoodzadeh, J. Shahrabi, M. Pariazar, and M. S. Zaeri, “Project selection by using fuzzy AHP and TOPSIS technique,” International Journal of Human and Social Sciences, vol. 1, no. 3, pp. 333–338, 2007. 7 R. P. Mohanty, R. Agarval, A. K. Choudhury, and M. K. Tiwari, “Application of fuzzy analytical network process to R & D project selection,” International Journal of Production Research, vol. 43, no. 24, pp. 5199–5216, 2005. 8 A. S. Alidi, “Use of the analytic hierarchy process to measure the initial viability of industrial projects,” International Journal of Project Management, vol. 14, no. 4, pp. 205–208, 1996. 9 D. Al-Rashdan, B. Al-Kloub, A. Dean, and T. Al-Shemmeri, “Environmental impact assessment and ranking the environmental projects in Jordan,” European Journal of Operational Research, vol. 118, no. 1, pp. 30–45, 1999. 10 N. Halouani, H. Chabchoub, and J. M. Martel, “PROMETHEE-MD-2T method for project selection,” European Journal of Operational Research, vol. 195, no. 3, pp. 841–849, 2009. 11 M. F. Abu-Taleb and B. Mareschal, “Water resources planning in the Middle East: application of the PROMETHEE V multicriteria method,” European Journal of Operational Research, vol. 81, no. 3, pp. 500–511, 1995. 12 A. D. Henriksen and A. J. Traynor, “A practical R&D project-selection scoring tool,” IEEE Transactions on Engineering Management, vol. 46, no. 2, pp. 158–170, 1999. 13 G. Mavrotas, D. Diakoulaki, and P. Capros, “Combined MCDA-IP Approach for Project Selection in the Electricity Market,” Annals of Operations Research, vol. 120, no. 1–4, pp. 159–170, 2003. 14 G. Mavrotas, D. Diakoulaki, and Y. Caloghirou, “Project prioritization under policy restrictions. A combination of MCDA with 0-1 programming,” European Journal of Operational Research, vol. 171, no. 1, pp. 296–308, 2006. 15 A. Salo, T. Gustafsson, and P. Mild, “Prospective evaluation of a cluster Program for Finnish forestry and forest industries,” International Transactions in Operational Research, vol. 11, pp. 139–154, 2004. 16 C. Kahraman, D. Ruan, and I. Doǧan, “Fuzzy group decision-making for facility location selection,” Information Sciences, vol. 157, no. 1–4, pp. 135–153, 2003. 17 B. D. Rouyendegh and S. Erol, “The DEA–FUZZY ANP department ranking model applied in Iran Amirkabir University,” Acta Polytechnica Hungarica, vol. 7, no. 4, pp. 103–114, 2010. 18 Ç. Kahraman, D. Ruan, and E. Tolga, “Capital budgeting techniques using discounted fuzzy versus probabilistic cash flows,” Information Sciences, vol. 142, no. 1–4, pp. 57–76, 2002. 19 K. T. Atanassov, “Intuitionistic fuzzy sets,” Fuzzy Sets and Systems, vol. 20, no. 1, pp. 87–96, 1986. 20 S. K. De, R. Biswas, and A. R. Roy, “An application of intuitionistic fuzzy sets in medical diagnosis,” Fuzzy Sets and Systems, vol. 117, no. 2, pp. 209–213, 2001. 21 E. Szmidt and J. Kacprzyk, “Intuitionistic fuzzy sets in some medical applications,” in Computational Intelligence. Theory and Applications, vol. 2206 of Lecture Notes in Computer Science, pp. 148–151, 2001. 22 E. Szmidt and J. Kacprzyk, “A similarity measure for intuitionistic fuzzy sets and its application in supporting medical diagnostic reasoning,” in Proceedings of the 7th International Conference on Artificial Intelligence and Soft Computing (ICAISC ’04), vol. 3070 of Lecture Notes in Computer Science, pp. 388–393, June 2004. 23 D. H. Hong and C. H. Choi, “Multicriteria fuzzy decision-making problems based on vague set theory,” Fuzzy Sets and Systems, vol. 114, no. 1, pp. 103–113, 2000. 24 E. Szmidt and J. Kacprzyk, “Using intuitionistic fuzzy sets in group decision making,” Control and Cybernetics, vol. 31, no. 4, pp. 1037–1053, 2002. 25 E. Szmidt and J. Kacprzyk, “A consensus-reaching process under intuitionistic fuzzy preference Journal of Applied Mathematics 15 relations,” International Journal of Intelligent Systems, vol. 18, no. 7, pp. 837–852, 2003. 26 K. I. Atanassov, G. Pasi, and R. Yager, “Intuitionistic fuzzy interpretations of multi-criteria multiperson and multi-measurement tool decision making,” International Journal of Systems Science, vol. 36, no. 14, pp. 859–868, 2005. 27 D. F. Li, “Multiattribute decision making models and methods using intuitionistic fuzzy sets,” Journal of Computer and System Sciences, vol. 70, no. 1, pp. 73–85, 2005. 28 H. W. Liu and G. J. Wang, “Multi-criteria decision-making methods based on intuitionistic fuzzy sets,” European Journal of Operational Research, vol. 179, no. 1, pp. 220–233, 2007. 29 Z. Xu, “Intuitionistic preference relations and their application in group decision making,” Information Sciences, vol. 177, no. 11, pp. 2363–2379, 2007. 30 Z. Xu, “Some similarity measures of intuitionistic fuzzy sets and their applications to multiple attribute decision making,” Fuzzy Optimization and Decision Making, vol. 6, no. 2, pp. 109–121, 2007. 31 Z. S. Xu, “Models for multiple attribute decision making with intuitionistic fuzzy information,” International Journal of Uncertainty, Fuzziness and Knowlege-Based Systems, vol. 15, no. 3, pp. 285–297, 2007. 32 L. Lin, X. H. Yuan, and Z. Q. Xia, “Multicriteria fuzzy decision-making methods based on intuitionistic fuzzy sets,” Journal of Computer and System Sciences, vol. 73, no. 1, pp. 84–88, 2007. 33 Z. Xu and R. R. Yager, “Dynamic intuitionistic fuzzy multi-attribute decison making,” International Journal of Approximate Reasoning, vol. 48, no. 1, pp. 246–262, 2008. 34 D. F. Li, “Extension of the LINMAP for multiattribute decision making under Atanassov’s intuitionistic fuzzy environment,” Fuzzy Optimization and Decision Making, vol. 7, no. 1, pp. 17–34, 2008. 35 G. W. Wei, “Maximizing deviation method for multiple attribute decision making in intuitionistic fuzzy setting,” Knowledge-Based Systems, vol. 21, no. 8, pp. 833–836, 2008. 36 Z. Xu and X. Cai, “Incomplete interval-valued intuitionistic fuzzy preference relations,” International Journal of General Systems, vol. 38, no. 8, pp. 871–886, 2009. 37 D. F. Li, Y. C. Wang, S. Liu, and F. Shan, “Fractional programming methodology for multi-attribute group decision-making using IFS,” Applied Soft Computing Journal, vol. 9, no. 1, pp. 219–225, 2009. 38 G. W. Wei, “Some geometric aggregation functions and their application to dynamic multiple attribute decision making in the intuitionistic fuzzy setting,” International Journal of Uncertainty, Fuzziness and Knowlege-Based Systems, vol. 17, no. 2, pp. 179–196, 2009. 39 M. Xia and Z. Xu, “Some new similarity measures for intuitionistic fuzzy value and their application in group decision making,” Journal of Systems Science and Systems Engineering, vol. 19, no. 4, pp. 430– 452, 2010. 40 Z. Xu and H. Hu, “Projection models for intuitionistic fuzzy multiple attribute decision making,” International Journal of Information Technology and Decision Making, vol. 9, no. 2, pp. 267–280, 2010. 41 Z. Xu and X. Cai, “Nonlinear optimization models for multiple attribute group decision making with intuitionistic fuzzy information,” International Journal of Intelligent Systems, vol. 25, no. 6, pp. 489–513, 2010. 42 C. Tan and X. Chen, “Intuitionistic fuzzy Choquet integral operator for multi-criteria decision making,” Expert Systems with Applications, vol. 37, no. 1, pp. 149–157, 2010. 43 Z. Xu, “A deviation-based approach to intuitionistic fuzzy multiple attribute group decision making,” Group Decision and Negotiation, vol. 19, no. 1, pp. 57–76, 2010. 44 J. H. Park, I. Y. Park, Y. C. Kwun, and X. Tan, “Extension of the TOPSIS method for decision making problems under interval-valued intuitionistic fuzzy environment,” Applied Mathematical Modelling, vol. 35, no. 5, pp. 2544–2556, 2011. 45 T. Y. Chen, H. P. Wang, and Y. Y. Lu, “A multicriteria group decision-making approach based on interval-valued intuitionistic fuzzy sets: a comparative perspective,” Expert Systems with Applications, vol. 38, no. 6, pp. 7647–7658, 2011. 46 M. Xia and Z. Xu, “Entropy/cross entropy-based group decision making under intuitionistic fuzzy environment,” Information Fusion, vol. 13, pp. 31–47, 2011. 47 D. Li and C. Cheng, “New similarity measures of intuitionistic fuzzy sets and application to pattern recognitions,” Pattern Recognition Letters, vol. 23, no. 1–3, pp. 221–225, 2002. 48 Z. Liang and P. Shi, “Similarity measures on intuitionistic fuzzy sets,” Pattern Recognition Letters, vol. 24, no. 15, pp. 2687–2693, 2003. 49 W. L. Hung and M. S. Yang, “Similarity measures of intuitionistic fuzzy sets based on Hausdorff distance,” Pattern Recognition Letters, vol. 25, no. 14, pp. 1603–1611, 2004. 50 W. Wang and X. Xin, “Distance measure between intuitionistic fuzzy sets,” Pattern Recognition Letters, vol. 26, no. 13, pp. 2063–2069, 2005. 16 Journal of Applied Mathematics 51 C. Zhang and H. Fu, “Similarity measures on three kinds of fuzzy sets,” Pattern Recognition Letters, vol. 27, no. 12, pp. 1307–1317, 2006. 52 I. K. Vlachos and G. D. Sergiadis, “Intuitionistic fuzzy information—applications to pattern recognition,” Pattern Recognition Letters, vol. 28, no. 2, pp. 197–206, 2007. 53 F. E. Boran, S. Genç, M. Kurt, and D. Akay, “A multi-criteria intuitionistic fuzzy group decision making for supplier selection with TOPSIS method,” Expert Systems with Applications, vol. 36, no. 8, pp. 11363–11368, 2009. 54 Kavita, S. P. Yadav, and S. Kumar, “A multi-criteria interval-valued intuitionistic fuzzy group decision making for supplier selection with TOPSIS method,” in Rough Sets, Fuzzy Sets, Data Mining and Granular Computing, vol. 5908, pp. 303–312, 2009. 55 F. Ye, “An extended TOPSIS method with interval-valued intuitionistic fuzzy numbers for virtual enterprise partner selection,” Expert Systems with Applications, vol. 7, no. 10, pp. 7050–7055, 2010. 56 F. E. Boran, S. Genç, and D. Akay, “Personnel selection based on intuitionistic fuzzy sets,” Human Factors and Ergonomics In Manufacturing, vol. 21, no. 5, pp. 493–503, 2011. 57 F. E. Boran, K. Boran, and T. Menlik, “The evaluation of renewable energy technologies for electricity generation in Turkey using intuitionistic fuzzy TOPSIS,” Energy Sources, Part B, vol. 7, pp. 81–90, 2012. 58 F. E. Boran, “An integrated intuitionistic fuzzy multi criteria decision making method for facility location selection,” Mathematical and Computational Applications, vol. 16, no. 2, pp. 487–496, 2011. 59 P. Wang, “QoS-aware web services selection with intuitionistic fuzzy set under consumer’s vague perception,” Expert Systems with Applications, vol. 36, no. 3, pp. 4460–4466, 2009. 60 M. H. Shu, C. H. Cheng, and J. R. Chang, “Using intuitionistic fuzzy sets for fault-tree analysis on printed circuit board assembly,” Microelectronics Reliability, vol. 46, no. 12, pp. 2139–2148, 2006. 61 V. C. Gerogiannis, P. Fitsillis, and A. D. Kameas, “Using combined intuitionistic fuzzy set-Topsis method for evaluating project and portfolio management information system,” IFIP Inernational Federation for Information Processing, vol. 364, pp. 67–81, 2011. 62 Z. Xu, “Intuitionistic fuzzy aggregation operators,” IEEE Transactions on Fuzzy Systems, vol. 15, no. 6, pp. 1179–1187, 2007. 63 K. T. Atanassov, Intuitionistic Fuzzy Sets, vol. 35 of Studies in Fuzziness and Soft Computing, PhysicaVerlag, Heidelberg, Germany, 1999. 64 E. Szmidt and J. Kacprzyk, “Distances between intuitionistic fuzzy sets,” Fuzzy Sets and Systems, vol. 114, no. 3, pp. 505–518, 2000. 65 P. Grzegorzewski, “Distances between intuitionistic fuzzy sets and/or interval-valued fuzzy sets based on the Hausdorff metric,” Fuzzy Sets and Systems, vol. 148, no. 2, pp. 319–328, 2004. 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